This will be the ULA’s 120th launch, the 72nd launch of the Atlas V, the 38th launch of the Atlas V in the 401 configuration. Launch window for this attempt will be open for 40 minutes.

The United Launch Alliance (ULA) Atlas V-400 Series rocket is a two-stage rocket that, depending on which of the three fairing sizes used, stands between 57.3 m (188 ft.) and 59.1 m (194 ft.) with a diameter of 12.5ft (3.81m) and consists of an Atlas Common Core Booster with a Russian RD-180 engine and first stage with a United States RL-10 Centaur upper stage built by AeroJet-Rocketdyne. The vehicle is available in 6 different configurations (when including the 500 series) which are built specifically for each individual mission. Its launch sites are Cape Canaveral Air Force Station (CCAFS), Launch Complex-41 (LC-41) or Vandenberg Air Force Base, Launch Complex-3 (LC-3).

Main Payload Fairing (PLF): The Main Payload Fairing for the Atlas-V-400 series is a two-shell fairing that can come in three configurations. All 4 m (13.8 ft.) in diameter, there’s the short option, known as the Large Payload Fairing (LPF) 39.3 ft. (12 m), the medium option, known as the Extended Payload Fairing (EPF) 42.3 ft. (12.9 m), and the largest option, known as the Extra Extended Payload Fairing (XPF) 45.2 ft. (13.8 m) option based on the payload. The fairings are used to protect the spacecraft & Centaur during its ascent through atmospheric turbulence and into space. Once the rocket has reached a safe altitude the fairings are pyrotechnically jettisoned via a debris-free actuating system.

Centaur Upper Stage: The Centaur Upper stage is 10 ft. (3.1 m) in diameter and 41.6 ft. (12.7 m) in length. It consists of a single Cryogenic RL-10C (RL-10C) Aerojet Rocketdyne Engine that provides 99.2 kN (22,300 lb.) of thrust and utilizes liquid hydrogen (LH2) for propellant and liquid oxygen (LOX) as an oxidizer with a burn time of up to 740 seconds to include multiple engine firings. There are also four 27-N (Newton) thrusters and eight 40-N (Newton) thrusters used for attitude control. Both utilize hydrazine as propellant. The Centaur Forward Adapter (CFA) provides structural mountings for vehicle electronics within the spacecraft.

Solid Rocket Booster’s (SRB’s): Have a diameter of 62.2 in. (158 cm) with a length of 65.6 ft. (20 m). The total number of SRB’s utilized is dependent on the individual mission and vary from none at all to 5. Each have a burn time of about 88.3 seconds.

Common Core Booster (CCB) (First-Stage): The American Atlas V Common Booster Core is 106.5 ft. (32.46 m) in length by 12.5 ft. (3.8 m) in diameter and is powered by a single two-chamber Russian RD-180 engine manufactured by NPO Energomash, that utilizes Rocket Propellant-1 (RP-1 or highly purified kerosene) as propellant and Liquid Oxygen (LOX) as the oxidizer. It provides 3,827 kN (860,300 lb.) of thrust at sea level and can burn for 311 seconds. The RD-180 engine is modeled after the 4-chanber RD-170 engines used by the Zenit rocket family.